In heavy construction, in creating supports between beams or walls for platforms or in pouring concrete structures, it is a common practice to use jacks to support the platforms of the forms or molds used in pouring concrete. In the case of creating concrete structures, the jacks are temporarily secured to steel or concrete beams, or to upright walls so as to provide a support for positioning the concrete forms so that they project beyond the beams or walls. After the jacks are mounted in place, the forms are supported on the jacks and the concrete is poured into the forms. After the concrete has set, the forms and the jacks may be removed so that the forms may be stripped from the poured concrete structures.
To facilitate removal of the jacks and the forms from the poured structures, the jacks are conventionally secured by a single rod which is anchored to the top of the beam or wall in an area which is accessible after the concrete is poured. When the jacks are mounted on the walls at a location removed from the exposed top, the jacks are commonly mounted by fasteners in the form of rods or bolts which pass into the wall and are anchored by nuts or other fasteners.
A typical jack is a triangular assembly having a top portion which extends horizontally from the support structure with an angularly extending strut portion which angles downwardly to provide vertical support, cantilever fashion, for the jack against the wall. The angular struts may be adjustable to accommodate to the various configurations which are necessary to provide the proper support for the cement forms used in the particular construction.
Although jacks are frequently constructed out of steel or another metal, it is not uncommon for jacks to be fabricated out of wood. Jacks may also be constructed from plastic materials or from any other type of material of sufficient strength to allow the jack to be used for the aforementioned functions.
Typically, the horizontal portion of the jack has a wooden plank attached to it for supporting the concrete forms. The wooden plank is often longer than the horizontal portion of the jack. The jack is typically in excess of four feet in length and may weigh over eighty pounds. Prior to the present invention, jacks were installed on the beam by a three-person crew, one person suspending the jack into the proper position adjoining the beam. The other two crew people are needed since it normally takes two people to make the attachments for securing the jack in place, particularly if the jack is positioned at some distance below the level of the beam or other support where there is a safe foothold.
Jacks are attached in sufficient quantity alongside and between parallel beams or other supports so that the planks provide a support on which to form a surface between said beams. A layer of concrete may be poured into forms resting on said surface or on a wooden platform resting on said surface, the concrete being set to create a deck alongside or between the beams. After the concrete has set, the jacks and any forms are removed.
This process of attaching jacks is hazardous and physically taxing on the crew because of the jack's bulk and weight, the adverse weather conditions that are frequently encountered in such outdoor work, and the height at which this process is often carried out. It is also an inefficient process as a jack is often not attached properly and has to be adjusted.